The Wildscreen festival is the world’s biggest celebration of screen-based natural history storytelling which takes place every two years in Bristol. Here: “Walrus in Midnight Sun”. Walrus feed mostly on bivalves in productive, shallow and often sandy habitats in the Arctic. This individual, though, arrived on a beach outside Tromsø, northern Norway, and found comfort on a stranded dead sperm whale. After two weeks he approached Audun, and only half a metre away he stretched his tusk forward and touched his hand gently. “This was one of the most memorable moments of my life”, Rikardsen says. He named the 500kg male Buddy. After two months, the dead whale was decomposed and Buddy suddenly disappeared. (Photo by Audun Rikardsen/Wildscreen 2016)

National Geographic invites photographers from around the world to enter the 2013 National Geographic Photography Contest. The grand-prize winner will receive $10,000 (USD) and a trip to National Geographic headquarters in Washington, D.C., to participate in the annual National Geographic Photography Seminar in January 2014. Photo: “We just want to move to search to the Leopard at that morning but we found a group of giraffes come toward a small lake and start drinking it was a nice moment when the Giraffe finish from drinking and leave a letters “S” with motion in the air”. (Photo and caption by Majed Ali/National Geographic Photography Contest)

Children watch and react as a T-Rex moves and growls in an inter-active display at Field Station Dinosaurs in Secaucus, N.J on May 25, 2012. There will be 31 types of life-sized dinosaurs displayed at the Jurassic expedition that opens Saturday, May 26. (Photo by Mel Evans/Associated Press)

A storm whips through a tented area occupied by Nepalese earthquake survivors as a mother grabs her infant child and runs to find shelter in Kathmandu, Nepal 23 May 2015. Nepalese, who lost their homes in earthquake and fear aftershocks, have been living in temporary shelter in open ground which they had to flee because of the heavy rain and powerful wind. (Photo by Narendra Shrestha/EPA)

Iranian demonstrators burn an Israeli flag during a rally marking al-Quds (Jerusalem) Day in Tehran July 10, 2015. (Photo by Reuters/Stringer/TIMA)

A British photographer has captured life at the “edge of the world”. Timothy Allen, best known for his work on BBC's Human Planet, trekked through the freezing Siberian wilderness for 16 days as he joined part of an 800km migration of reindeer in the Yamal-Nenets region – a name that roughly translates to “edge of the world”. The stunning pictures feature the nomadic Nenets tribe, who drink blood to survive in -45°C temperatures. Timothy's epic journey, which will be revealed in an eight-minute documentary on Animal Planet USA, saw him travel across the bleak terrain of the frozen Ob River with the Nenets people in December last year. Here: An empty camp is shown beneath a colourful sky in Siberia, December 2016. (Photo by Timothy Allen/Barcroft Productions)

Sisters await the arrival of the caravan carrying the late Cuban President Fidel Castro's ashes in El Maja, Cuba, December 1, 2016. (Photo by Edgard Garrido/Reuters)

Members of the Albert Battery perform a gun salute during the Anzac Day dawn service held by the Currumbin RSL on the Gold Coast in Currumbin, Australia, 25 April 2016. The Anzac day marks the landing of the Australian and New Zealand Army Corps (Anzac) troops at Gallipoli in what is today Turkey during WWI. World War One, also called the Great War, according to official statistics cost more than 37 million military and civilian casualties between 1914 and 1918. (Photo by Glenn Hunt/EPA)